Cost-effective dense deployment is an important enabler of long-term evolution (LTE) and fifth generation (5G) wireless networks. So-called small cells, access nodes (also referred to as access points or base stations) that each serves a number of proximally located user equipment (UE) terminals with a lower transmit power than conventional base stations, are effective in supporting ultra-dense broadband access. Each small cell is connected to core network via a backhaul connection.
One technique for deploying small cells comprises the placement of radio base stations, oftentimes called evolved node B (eNB) in LTE and next generation node B (gNB) 5G terminology, on lampposts distributed along a street. Electrical connections are already available at each lamppost to power lights, and can conveniently be used provide power to the eNBs. Providing wired backhaul access (e.g. using optical fiber) to a large number of lamppost-based base stations may be logistically difficult unless done during the construction of the street on which the nodes are deployed. A simpler solution is to provide backhaul connectivity to couple a first lamppost-based base station in a series to a core network. Each base station in the series can be wirelessly connected to adjacent base stations, creating a multihop connection to the first base station, which has the wired backhaul connection. In some embodiments, the wireless connection between base stations may use unlicensed wireless spectrum.
In such setups, it will be recognized that the lamppost mounted base stations are often in a straight line, resulting in interference between segments. Improvements are needed to mitigate interference over wireless spectrum used for daisy-chained base stations.